Are the level densities for r- and rp-process nuclei different from nearbynuclei in the valley of stability? art. no. 065803

Nuclei reached in r- and rp-process reactions in nuclear astrophysics are c onsiderably more neutron or proton rich than most nuclei for which level de nsities have been studied. Two models which predict somewhat different beha vior for nuclei away from the valley of stability are examined. It is found that one of the two provides a better description of the available data. A term which lowered the level density parameter as isospin increased at fix ed A did not produce as much improvement as one which reduced the level den sity parameter based on the distance from the valley of stability. As a by- product of this study, a formulation of level density systematics near the valley of stability is also tested.